Project Loon, an initiative of X (formerly Google X), seeks to provide internet access to rural and remote areas by using high-altitude balloons. The balloons, residing in the stratosphere (~18 km), would form an aerial wireless network providing LTE-like coverage. Balloons navigate by changing their altitudes to find winds of appropriate direction.
The initiative, active since 2008, has tested balloons in six continents, most recently providing bandwidth to flooded areas in Peru. Project Loon also claims that through artificial intelligence technology from Alphabet, the balloons have become much more efficient, requiring far fewer for coverage.